Fabric softener kills microfibre towels, not the washing machine

A drying towel that stops taking up water after its third wash and skids across the paint like a sheet of paper. If that has happened to you, you probably blamed the towel. Nearly every time the cause is in the washing machine, in one drawer you fill out of habit. There is time before the next dry window for the exterior wash to get your towels washed so they grip again.

Washing microfibre towels means lifting polish, wax and limescale out of the split fibres without melting the fibre tips. You get there with a softener-free specialist detergent, 40 °C on a delicate cycle, a low spin and air drying. Softener, powder and heat above 60 °C destroy exactly what makes a towel a towel.

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Microfibre cleans mechanically, so every free fibre tip counts

A microfibre towel cleans mechanically, not chemically: millions of split fibre tips grab dirt particles and pull water into the weave by capillary action, as long as the gaps between the fibres stay open.

In the textile trade a microfibre is any fibre finer than one decitex, far finer than a human hair. During manufacture each fibre is split lengthways into wedge-shaped segments. That split is what creates the hollows and edges that make a towel absorbent and grippy. An unsplit polyester yarn would just be smooth and push water ahead of it.

The blend decides the character. Polyester loves oil and brings stability, polyamide takes up water and keeps the pile soft. A polyester-heavy weave like the Dr. Wack A1 "DAS TUCH" Premium Mikrofaser Mikrofasertuch at 85/15 lasts longer and suits glass and interiors. A weave with a high polyamide share like the THE COLLECTION "Aqua" Twisted Loop Trockentuch (1500 GSM) at 70/30 drinks more and stays softer.

So washing is nothing more than opening those hollows back up. Polish, wax, silicone oil from tyre dressing and the dust from the cabin lodge between the fibre tips. While they sit there, water runs across the towel, and when you dry the car the towel pushes grit ahead of it. Which towel is built for which surface is covered in the post on weight class in GSM.

How often you need to wash microfibre towels depends on the surface. A towel that has pulled polish or sealant off the paint gets washed after every use. A drying towel that has only taken up clean water is good for two or three drying sessions before it goes in the drum. Interior towels sit in between, because dust and plastic dressing clog the pile faster than water does.

Without the right wash, your drying towel becomes a scratch risk

Fabric softener, cotton in the same drum and heat above 60 °C destroy the capillaries of microfibre, and a towel without capillaries scratches the clear coat instead of soaking.

Softener is made of cationic surfactants, so-called esterquats. They wrap every fibre in a waxy film, which is exactly what makes cotton bath towels fluffy. On microfibre that same film seals the gaps between the fibre tips. The towel feels soft but repels water and drags streaks across glass. A single wash with softener is enough, and the film lasts for several washes.

Cotton in the same load is the second classic. Split microfibre works like a lint magnet in the drum and pulls fluff out of bath towels and jeans into its pile. That fluff comes loose again on the paint the next time you dry. So microfibre towels always get their own load, even if that means three towels in a mesh bag.

Polyester only melts at around 250 °C, but the split fibre tips have so little mass that they lose their shape from 60 °C upwards. On a hot tumble-dry setting they fuse into hard little beads you can feel with a fingertip as roughness. On black paint a towel like that leaves fine scratches you only notice in sunlight.

The maths is simple. Under good conditions a towel of split 70/30 fibre survives 80 to 150 washes. A towel that has seen softener three times and one hot tumble is a wheel rag after four washes. Between those two there is no product, only the question of what goes in the softener drawer and how hot the drum runs.

Sort by surface and pre-soak your polish towels first

Step one is sorting by surface, so paint, interior and wheels stay apart. Step two is a pre-soak for heavily loaded towels in warm water with 50 ml of specialist detergent.

You sort by what the towel has taken up, not by colour. Drying towels and towels for polish and sealant form the first group, they touch the clear coat. Interior towels with plastic dressing and leather cleaner are the second. Wheel towels, towels with tar remover and the wash mitt from the sills are the third. These three groups never share a drum, because silicone oil and brake dust travel through the wash water into every other textile.

The wash mitt gets its own cycle, and that goes for all wash mitts alike. A mitt like the TUGA Chemie Waschhandschuh (Mikrofaser) für "Shampoo-Teufel" with 95 percent polyester picks up sand and insect remains while you wash the car, and none of that belongs in a drying towel. The maker specifies 40 °C without softener and wants it air dried. The same goes for the Koch-Chemie Exterior Wash Mitt 640GSM Mikrofaser Waschhandschuh with its denser pile.

Towels that have taken off polish residue, wax or a ceramic coating do not go into the machine dry. For heavily soiled towels SONAX recommends a bucket of warm water with 50 ml of SONAX PROFILINE Microfibre Wash Mikrofaserwaschmittel for soaking. The reason is time: silicone oils and silica particles need minutes in the surfactant before they let go of the fibre, not the brief contact of a running cycle.

Coating towels are the special case. A ceramic coating cures in air, inside the fibre too. A towel left lying dry overnight has glass-hard crystals in its pile by morning and no longer belongs anywhere near paint. So it goes into water straight after buffing off. And every new towel gets a first wash before its first use, to get rid of finishing agents and loose fibres from production. Dr. Wack writes exactly that into the care guide for the A1 "DAS TUCH".

If you are not getting to the exterior wash over the next few days anyway, this is the right time for it. Here in Nordhorn rain is moving through after the clear morning, and the next reliably dry window is forecast for Monday, 21 September. By then the towels are washed, dried and sorted again.

Wash at 40 °C on a delicate cycle and dry in the air

Microfibre towels are washed with a liquid specialist detergent at 40 °C on a delicate cycle, spun at no more than 600 to 800 rpm and dried in the air or on a low tumble setting.

If you want to wash microfibre towels properly, the real decision is the detergent. A microfibre-specific detergent is free of optical brighteners, bleach, fragrance and softening agents and carries surfactants built for oils, waxes and polymers. According to SONAX, the Microfibre Wash lifts polish, wax, silicone and coating residue and is rated as a high concentrate for 50 washes per litre, which works out at about 20 ml per load.

A liquid colour detergent without fragrance or dyes will do in a pinch, but it is weaker against wax. Powder detergent is out: it contains zeolites as water softeners, insoluble mineral particles that lodge in the pile and act like fine sand on the next wipe. Detergent with built-in softener is off limits for the reason above, however the label phrases it.

Temperature follows a simple ladder. 30 °C is enough for glass and drying towels that have only seen water and glass cleaner. 40 °C on a delicate cycle is the standard for anything that has taken up detailer, interior dressing or light spray wax, which is what SONAX recommends for the Microfibre Wash. Only polish towels and wax removal towels need 60 °C, because that is where the wax finally melts. Dr. Wack clears the A1 "DAS TUCH" for up to 60 °C without bleach.

With spin it comes down to the pull on the pile. SONAX names 600 rpm as the upper limit, other makers allow up to 1,000. We stay at 600 to 800: the towel comes out of the drum wetter, but the twisted-loop pile of a 1500 GSM drying towel keeps its shape instead of coming out crushed and twisted.

The gentlest way to dry is in the air, on a clothes horse and not on a radiator. The tumble dryer is fine if it runs cold or on its lowest setting with no dryer sheets in it, because those are nothing but softener in paper form. Dr. Wack allows up to 60 °C in the dryer for the A1 towel followed by a shake-out, TUGA wants the wash mitt air dried only.

A stiff towel is usually scaled up, not worn out

A microfibre towel that goes stiff and repels water is in most cases not destroyed but clogged with lime soap and surfactant residue, and a wash with vinegar in the softener drawer dissolves that.

Hard tap water carries calcium and magnesium ions. They bind with detergent residue that never quite rinses out of the pile into insoluble lime soap. The deposit settles into the gaps of the fibre, the towel feels like cardboard and pushes water droplets ahead of it. From the outside that looks like a towel at the end of its life, and that is usually how it gets binned.

The rescue is acetic acid. 50 to 100 ml of clear household vinegar goes into the softener drawer, followed by a 40 °C wash with half a dose of specialist detergent. The acid dissolves the lime soap and neutralises the surfactant residue. Then comes a second wash without vinegar so the smell does not stay in the towel. With a softener history the vinegar only gets you part of the way, that takes two or three washes with specialist detergent, and not every towel comes all the way back.

The mistake that really ends a towel has nothing to do with washing. If a drying towel hits the floor, it picks up sand and quartz grains in that instant, and no wash pulls all of them back out. A towel like that changes group on the spot and works on wheels or exhaust tips from then on. The same goes for a towel that accidentally went in with cotton or through a hot dryer.

That demotion is the real care plan in practice. A new towel starts on paint, on polish, sealant and glass. Once the pile looks slightly compressed, often after 20 to 30 washes, it moves to the interior. When it goes stiff or discoloured it takes over wheel barrels, door shuts and tyre sidewalls. Torn or gummed up, it becomes a rag for oil spills. That way a tired towel never scratches where it hurts.

One litre of concentrate covers 50 washes and four towel classes

The starter setup for towel care is one litre of softener-free specialist detergent, a mesh laundry bag and separate loads for paint, interior and wheels, and at the start that is all you need.

For detergent the road leads to the SONAX PROFILINE Microfibre Wash Mikrofaserwaschmittel in the 1-litre bottle. It is rated as a high concentrate for 50 washes and, according to SONAX, made specifically for microfibre towels and polishing pads, which get washed separately. For a household with ten to twenty towels and one load a week the bottle works out at a year.

For drying towels the rule is: the higher the polyamide share, the more water it takes up and the more sensitive it is to heat. The THE COLLECTION "Aqua" Twisted Loop Trockentuch (1500 GSM) in the "Big" size at 50 x 80 cm takes up a whole bonnet at 70/30 without being wrung out, and for exactly that reason wants 30 to 40 °C and a low spin.

The "Mini" size at 40 x 40 cm handles door shuts and mirrors. On Trusted Shops the Aqua sits at three reviews so far, all five stars. Both sizes get washed together, but never with the wash mitt that cleaned the bonnet beforehand.

For interior and glass a firmer weave works better. The Dr. Wack A1 "DAS TUCH" Premium Mikrofaser Mikrofasertuch with 85 percent polyester has less pile but more edge, and according to its care guide takes 60 °C and the dryer. It is the towel that most often goes through our 60 °C round, because it takes off polish residue before the drying towel ever touches the paint.

The wash mitt completes the set and gets its own cycle at 40 °C. If you want to see all four towel classes side by side, the full range is in the microfibre towels collection. How drying without scratches works afterwards is in the post on drying the car without scratches.

Detailing1 insight: In our showroom every towel that has taken polish or sealant off the paint of the BMW M5 goes into a bucket of warm water with 50 ml of Microfibre Wash the same evening. Once a coating towel was left lying dry overnight. By morning the pile was glassy at the edges, the towel visibly dragged on the black paint, and today it is a wheel towel. And run your palm over the towel before every wash: if it feels like cardboard, it goes into the vinegar round.